1. Field of the Invention
The invention relates to the field of dynamic magnetic information storage and retrieval. More particularly, the invention relates to a magnetic recording head. In still greater particularity, the invention relates to a method and apparatus for securing a closure to a recording module. By way of further characterization, but not by way of limitation thereto, the invention utilizes gluing vias in the closure and or in the recording module to strengthen the bond therebetween.
2. Description of the Related Art
There has been a great demand for increasing the data throughput of magnetic tape transport systems used in conjunction with high-speed digital computers. In order to utilize the high-speed capabilities of these computers, it is necessary to increase the amount of data stored on a magnetic tape and to increase the speed at which the data is written to or retrieved from the magnetic tape media.
To increase the data storage capacity of the tape transport systems, the areal density of the magnetic tape media which stores the data must be increased. Areal density is defined as the number of units of data stored in a unit area of the tape. Areal density is characterized by two attributes: linear density and track density. To increase the areal density of a magnetic tape media, one must increase either or both, the linear density and track density of the magnetic tape.
Track density is defined as the number of data tracks per unit width of magnetic tape. Two characteristics associated with track density are track width, defined as the actual width of an individual data track; and track pitch, defined as the distance from the center of one data track to the center of a neighboring data track. As magnetic tape head size decreases, the track pitch and track width are decreased, thereby increasing track density.
With high track density magnetic recording heads such as in the 36-track system, because the distance between data tracks is reduced, slight imperfections in the heads will have a more significant impact on the performance and/or the quality of the tape heads. Naturally, a small imperfection in a small area will have a greater impact and be more significant than the same small imperfection in a larger area.
In magnetic recording heads, especially magneto-resistive thin-film tape heads, a gap length between a substrate and a closure is one of the critical parameters in determining the recording performance of the tape head. Bonding the closure and the recording module affects the gap which is critical to the performance of the head. When an adhesive is introduced between the recording module and the closure, an insufficient bond will result in a condition known in the art as "gap slip". Gap slip allows shifting of the closure with respect to the recording module and results in significant yield problems in tape head manufacturing. The occurrence of gap slip during head operation would also deteriorate the head recording performance and head life.
The substrate has read and/or write tracks deposited on and extending from a gap side surface of the substrate to form the recording module which has a nonplanar topography due to the deposition of the structured thin film layers. The recording module is bonded to the flat surface on the closure. After bonding the closure and the recording module, the tape head is ground and lapped such that a smooth contoured surface is obtained.